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Taj Bahadori Page 6 of 8 August 30, 2018 and a new permit from the San Joaquin Valley Air Pollution Control District (SJVAPCD) must be in place before additional landfill gas can be recovered. The proposed LFG extraction wells will be constructed in accordance with the existing LFG extraction well designs. The extraction well locations are provided on Figure 3 along with each well's proposed well schedule. The extraction wells will consist of a 36 -inch diameter boring drilled to a bore depth of approximately 75 -percent of the waste thickness to minimize any potential damage to the liner system. The extraction well casing will be constructed of 6 -inch diameter high-density polyethylene pipe with a standard dimension ratio of 17. The top of the casing will stick-up approximately 3 feet above the ground surface and will be equipped with a wellhead assembly to control the extraction rate of the landfill gas being pulled through the well. The below ground portion of the well casing will continue with 30 more feet of solid piping to help prevent any potential air infiltration from the surface. The remainder of the well casing will be perforated with an end cap sealing the bottom of the pipe. The space between the well casing and the boring will consist of a series of bentonite plugs and on-site soils around the length of the solid piping to again help prevent any potential air infiltration from the surface. The perforated section will be encased in a coarse aggregate to allow the maximum extraction surface area for the well. Proposed well locations and standard details are shown on Figure 3. There are currently four proposed extraction wells, three wells in Module "I" and one in Module 1 (Figure 3). The three wells proposed in Module "I" are located northeast of MW - 3 in the deepest part of the closed landfill to further increase the density of the LFG extraction wells to further mitigate LFG constituents contributing to groundwater contamination. One additional well is proposed in newer waste of Module 1. The proposed LFG extraction wells are anticipated to be constructed concurrently with the new LFG flare. Below is the tentative schedule for the solicitation, permitting, and installation of new flare and LFG extraction wells. Note that this construction schedule is subject to change based on obtaining permits from SJVAPCD. The RWQCB will be notified of any delays. 083018 FH-RWQC13-Revised Work Plan_Final.doex